Synthesis and Physicochemical Characterization of Fluorescent (E)‐2‐Stilbenyloxyalkylthiouracils and Isomer Differentiation Using EIMS.

Abstract

Twelve new fluorescent (E)-2-stilbenyloxyalkylthiouracils and 6-methyluracils 5a-5l were prepared. EI induced mass spectral fragmentation of these compounds was investigated. Fragmentation pathways are proposed on the basis of accurate mass and metastable transition measurements. Correlation between the intensities of the M +. and the selected fragment ions of these compounds is discussed. The data obtained permit a distinction of the metamers. The 1 H and 13 C NMR spectra of these compounds were assigned unambiguously using a combination of heteronuclear (HETCOR) spectra and the chemical shifts. The data derived from these spectra can be used to differentiate the isomers.

From 2-Triethylammonium Ethyl Ether of 4-Stilbenol (MG624) to Selective Small-Molecule Antagonists of Human α9α10 Nicotinic Receptor by Modifications at the Ammonium Ethyl Residue

“…R f (cyclohexane/EtOAc 9:1) = 0.53. mp = 130 °C. (coherent with literature 24 6.90 (d, J = 8.8 Hz, 2H), 4.28 (t, J = 6.9 Hz, 2H), 3.43 (t, J = 6.9 Hz, 2H).…”

“…As in our previous investigation on onium-alkyloxy-stilbene based compounds, the pharmacological characterization of this new series of stilbenol ammoniumalkyl ethers, formally derived from the lead 1 by modification of the cationic head (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17) or rigidification of the O-N linker (18)(19)(20)(21)(22)(23)(24)(25)(26)(27), started from the evaluation of the α7-nAChR binding affinity by α-Bgtx displacement. This is indicative of competition for the same ACh orthosteric binding sites of this receptor and, in the development of our investigation, a useful guiding criterion in selecting candidates for functional study at both α7and α9α10-nAChR.…”

Potent Antiglioblastoma Agents by Hybridizing the Onium-Alkyloxy-Stilbene Based Structures of an α7-nAChR, α9-nAChR Antagonist and of a Pro-Oxidant Mitocan

“…The intermediates 4b−i were synthesized according to a modified literature procedure. 22 A solution of trans-4-hydroxy-stilbene (1 mmol) in DMSO (1.4 mL) was added to a stirred suspension of 85 mg of finely ground NaOH (2.1 mmol) in DMSO (5.6 mL). The mixture was stirred at room temperature (RT) for 30 min and then the appropriate dibromoalkane (2 mmol) was added dropwise.…”